Here is the back cover of Barbra's 1977 album Superman. I worked at a music store in NYC that year (Carl Fischer Music Publisher) and the sheet music, with Barbra in her revealing outfit, flew off the shelves.
The cover, was probably the raciest thing she ever did. . .until perhaps Meet The Fokkers, where she plays the nearly deranged sex-therapist mom of Ben Stiller (Fokker)... ---o0o---